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Upon temperature downshift below the lower threshold of balanced growth (~20°C), the Escherichia coli translational apparatus undergoes modifications allowing the selective translation of the transcripts of cold shock-induced genes, while bulk protein synthesis is drastically reduced. Here we were able to reproduce this translational bias in E. coli cell-free extracts prepared at various times during cold adaptation which were found to display different capacities to translate different types of mRNAs as a function of temperature. Several causes were found to contribute to the cold-shock translational bias: Cold-shock mRNAs contain cis-elements, making them intrinsically more prone to being translated in the cold, and they are selective targets for trans-acting factors present in increased amounts in the translational apparatus of cold-shocked cells. CspA was found to be among these trans-acting factors. In addition to inducing a higher level of CspA, cold shock was found to cause a strong (two- to threefold) stoichiometric imbalance of the ratio between initiation factors (IF1, IF2, IF3) and ribosomes without altering the stoichiometric ratio between the factors themselves. The most important sources of cold-shock translational bias is IF3, which strongly and selectively favors translation of cold-shock mRNAs in the cold. IF1 and the RNA chaperone CspA, which stimulate translation preferentially in the cold without mRNA selectivity, can also contribute to the translational bias. Finally, in contrast to a previous claim, translation of cold-shock cspA mRNA in the cold was found to be as sensitive as that of a non-cold-shock mRNA to both chloramphenicol and kanamycin inhibition.

If it's true that by age 50 we all get the faces we deserve, it is also true that no such grimly satisfying rule applies to biography. There and there alone does the hapless subject, living or dead, remain uniquely at the mercy of whoever chooses to tell his tale and hence uniquely at the mercy of the biographer's motivations, high and low. Some such storytellers, for example, strive to elevate themselves by throwing great men and women down (a genre that Joyce Carol Oates has dubbed 'pathography'). Others, such as those specializing in celebrity tell-alls, sort the dirty laundry of their subjects for more straightforward reasons: to pay their own rent. Then there are the closet narcissists who thrash out their own selves between the lines of the stories of others as when melancholics are drawn to interpreting the life of Lincoln, say, or professional political enemies to rewriting the lives of their adversaries. Adapted from the source document.